Barcodes are used throughout supply chains to identify objects, collect data about objects, and enter data into computer systems. There are many different types of barcodes, but can generally group them into two categories: Linear, or one-dimensional barcodes, and 2D or two-dimensional barcodes. One dimensional barcodes provide information along one axis, similar to a standard alphanumeric sentence. Two dimensional barcodes provide information along two axes, similar to a matrix. Regardless of the type of bar code used, to maintain the integrity of a barcode system, the barcodes in use must be of sufficient quality such that barcode readers can decipher them. Accordingly, users of barcodes have created standards bodies that have promulgated various standards to insure that barcodes meet certain quality requirements.
Barcode verification is the process by which barcodes are examined to determine whether or not barcodes meet industry standards. Barcode verifiers are used to perform barcode verification by taking an image of the barcode and performing various tests on it. This process is outlined in barcode verifier standards ISO/IEC 15416:2000 (for linear bar code verifiers) and ISO/IEC 15415:2004 (for two dimensional bar code verifiers), both publications of which are hereby incorporated by reference. Other technical standards that are relevant to bar codes and to the present application are ISO/IEC15426-1:2006, ISO/IEC15426-2:2005, ISO 15394:2000(E), ATA SPEC 2000, NDC 2001, MIL-STD-130L, and the GS1 General Specifications, all of which are hereby incorporated by reference.
When using a handheld barcode verifier, it is necessary for the user to scan the verifier across the barcode in order to obtain the image. For linear barcode verification, this is relatively straightforward because the information is only provided along the X axis. Any defect in the image along the Y axis (e.g. skewing of the image due to the user's hand movement) will not, to any large degree, affect the verifier's ability to accurately verify the barcode. With respect to two dimensional barcodes, however, it is important that the barcode image not contain defects along the Y axis. Furthermore, due to the more dense nature of two dimensional barcodes, it is important that the barcode verify have sufficient resolution that it captures a sufficient amount of the barcode that verification can occur. Most two-dimensional barcode verifiers rely on an area scan camera which is expensive and requires multiple lenses to inspect various sizes of bar codes. In order to have sufficient resolution of small bar codes, a lens will be required that zooms in on the barcode sample while different lenses will be required for medium and large bar codes. The image scanning apparatus and methods of the present application provide the ability to capture any common sized linear or two-dimensional without changing lenses or reconfiguring the barcode verifier.